1. Field of the Invention (Technical Field)
Embodiments of the present invention relates to a system and method for sample handling and analysis of a continuous flow of samples by a particle analyzer.
2. Description of Related Art
Note that the following discussion refers to a number of publications by author(s) and year of publication, and that due to recent publication dates certain publications are not to be considered as prior art vis-a-vis embodiments of the present invention. Discussion of such publications herein is given for more complete background and is not to be construed as an admission that such publications are prior art for patentability determination purposes.
Flow cytometers are used to analyze biological cells and particles in a fluid sample by intersecting a thin stream of the fluid sample by an illumination source, usually a laser beam. The resulting light scatter (forward and right angle (side) scattered light) and fluorescent light is analyzed with one or more photomultiplier tubes (PMTS). The fluorescence channels of a flow cytometer are each set with barrier filters to detect a selected specific dye having a desired wavelength while filtering out signals from other wavelengths.
U.S. Pat. Nos. 4,714,682, 4,767,206, and 4,774,189, and U.K. Pat. No. 2,172,104 describe calibration of a flow cytometer using highly uniform microbeads which have excitation and emission spectra that match that of the unknown samples, as well as describing the synthesis and composition of said highly uniform microbeads. Matching spectra of microbeads and cells in this way allows direct comparison of data among flow cytometers which have different barrier filters so long as the sample and the calibration microbeads are analyzed under comparable instrument conditions and settings. Each sample that flows past the illumination source and is detected by the photomultiplier tube is recorded as a separate data file for analysis.
U.S. Pat. No. 5,084,394 describes the combined use of calibrated fluorescent biological cells with calibrated fluorescent microbeads to compensate for different responses of different flow cytometers. U.S. Pat. Nos. 6,074,879 and 6,350,619 describes novel methods for calibrating or standardizing flow cytometry instruments using synthetic polymer particles or beads having physical properties which provide advantages for their use in such instruments.
All of these methods require that a separate data file is obtained for each separate sample analyzed and therefore there is no difficulty in identifying the beginning and end for each sample even though the number of particle events within the sample are low. The totality of these patents and all other patents and any other publications cited herein and/or referred to in the Cross-Reference to Related Applications is hereby incorporated herein by reference.